共查询到20条相似文献,搜索用时 15 毫秒
1.
Caroline de Gracia Lux Jean‐Louis Gallani Dr. Gilles Waton Dr. Marie Pierre Krafft Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(24):7186-7198
Understanding and controlling the molecular organization of amphiphilic molecules at interfaces is essential for materials and biological sciences. When spread on water, the model amphiphiles constituted by CnF2n+1CmH2m+1 (FnHm) diblocks spontaneously self‐assemble into surface hemimicelles. Therefore, compression of monolayers of FnHm diblocks is actually a compression of nanometric objects. Langmuir films of F8H16, F8H18, F8H20, and F10H16 can actually be compressed far beyond the “collapse” of their monolayers at ~30 Å2. For molecular areas A between 30 and 10 Å2, a partially reversible, 2D/3D transition occurs between a monolayer of surface micelles and a multilayer that coexist on a large plateau. For A<10 Å2, surface pressure increases again, reaching up to ~48 mN m?1 before the film eventually collapses. Brewster angle microscopy and AFM indicate a several‐fold increase in film thickness when scanning through the 2D/3D coexistence plateau. Compression beyond the plateau leads to a further increase in film thickness and, eventually, to film disruption. Reversibility was assessed by using compression–expansion cycles. AFM of F8H20 films shows that the initial monolayer of micelles is progressively covered by one (and eventually two) bilayers, which leads to a hitherto unknown organized composite arrangement. Compression of films of the more rigid F10H16 results in crystalline‐like inflorescences. For both diblocks, a hexagonal array of surface micelles is consistently seen, even when the 3D structures eventually disrupt, which means that this monolayer persists throughout the compression experiments. Two examples of pressure‐driven transformations of films of self‐assembled objects are thus provided. These observations further illustrate the powerful self‐assembling capacity of perfluoroalkyl chains. 相似文献
2.
Ionic Self‐Assembly and Red‐Phosphorescence Properties of a Charged Platinum(II) 8‐Quinolinol Complex Associated with Ammonium‐Based Amphiphiles
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Dr. Franck Camerel Dr. Antoine Vacher Dr. Olivier Jeannin Prof. Joaquín Barberá Dr. Marc Fourmigué 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(52):19149-19158
A series of ionic associates based on the platinum(II) chelate of 5‐sulfo‐8‐quinolinol, [Pt(qS)2]2?, and ammonium‐based amphiphiles is described. At variance with the prototypical neutral complex Pt(q)2 (q=8‐quinolinol), these dianionic fluorophores, functionalized at the periphery with sulfonate groups, can be associated by the ionic self‐assembly approach with various ammonium cations, such as (H2 n+1Cn)2Me2N+ (n=12, 16, 18) or complex ammonium cations carrying three Cn carbon chains (n=12, 14, 16) and an additional amide group. Investigations of their luminescence properties in solution, in the solid state, and, when possible, in thin films revealed that the phosphorescence properties in condensed phases are directly correlated to intermolecular interactions between the luminescent [Pt(qS)2]2? centers. Of particular interest is also the formation of a columnar liquid‐crystalline phase around room temperature (between ?25 and +180 °C), as well as the very good film‐forming ability of some of these fluorophores from organic solvents. 相似文献
3.
Usingn-hexadecyl acrylate, surface pressure-area (F-A) curves and equilibrium spreading pressuresF
e were measured at various temperatures (5.7°–46°C) by the Langmuir balance (F-A) and the Wilhelmy-plate method (F
e). At low temperatures (T<13 °C) condensed films and the liquid-condensed/solid condensed transition can be observed. At high temperatures (T>30 °C) liquid-expanded films occur. In the intermediate range the compression curves have two transition points. The transition pressureF
1 between liquid-expanded and condensed film has a marked temperature dependence. The transition enthalpiesH
1 decrease with increasing temperature and become zero at 29.2 °C. The second transition is related to a transition between the condensed films (F
2). The slight temperature dependence of this transition is accompanied by an increasing change of area as well as by increasing transition enthalpiesH
2.TheF
e-T curve has two distinct breaks, at the melting pointT
m and atT=30 °C. The break atT
m is due to the melting process and the break atT=30 °C is caused by a phase transition between a liquid-expanded film and a condensed film.The phase diagram was constructed from the transition pressures. It can be demonstrated that the highest pressures of the thermodynamic stable film occurs atT
m. At temperaturesT>T
m equilibrium spreading pressure and equilibrium collapse pressure are identical whereas atT
m supercompression of the monolayer occurs. The film in this state behaves like a supercooled liquid. Obviously, rupture and collapse of such a film lead to a thermodynamically metastable bulk phase. 相似文献
4.
Hui Chen Lu Zhou Xiang Shi Jun Hu Jia Guo Pierre‐Antoine Albouy Min‐Hui Li 《化学:亚洲杂志》2019,14(6):781-788
A series of aggregation‐induced emission (AIE) fluorescent gelators (TPE‐Cn‐Chol) were synthesized by attaching tetraphenylethylene (TPE) to cholesterol through an alkyl chain. The properties of the gel, nano‐/microaggregate, and condensed phases were studied carefully. TPE‐Cn‐Chol molecules form AIE fluorescent gels in acetone and in DMF. Their fluorescence can be reversibly switched between the “on” and “off” states by a gel–sol phase transition upon thermal treatment. The AIE properties of aggregated nano‐/microstructures in acetone/water mixtures with different water fractions were studied by using fluorescence spectrometry and scanning electron microscopy (SEM). In different acetone/water mixtures, the TPE‐Cn‐Chol molecules formed different nano‐/microaggregates, such as rodlike crystallites and spherical nanoparticles that showed different fluorescence colors. Finally, the condensed phase behavior of TPE‐Cn‐Chol was studied by using polarizing microscopy (POM), differential scanning calorimetry (DSC), fluorescence spectrometry, fluorescence optical microscopy, and wide‐angle X ray scattering (WAXS). The clover‐shaped TPE unit introduced into the rodlike cholesterol mesogen inhibits not only the formation of a liquid‐crystal phase but also recrystallization upon cooling from the isotropic liquid phase. Very interestingly, TPE‐Cn‐Chol molecules in the condensed state change their fluorescence color under external stimuli, such as melting, grinding, and solvent fuming. The phase transition is the origin of these thermo‐, mechano‐, and vapochromic properties. These findings offer a simple and interesting platform for the creation of multistimuli‐responsive fluorescent sensors. 相似文献
5.
《Acta Crystallographica. Section C, Structural Chemistry》2018,74(10):1171-1179
3,5‐Bis(arylidene)‐4‐piperidone (BAP) derivatives display good antitumour and anti‐inflammatory activities because of their double α,β‐unsaturated ketone structural characteristics. If N‐benzenesulfonyl substituents are introduced into BAPs, the configuration of the BAPs would change significantly and their anti‐inflammatory activities should improve. Four N‐benzenesulfonyl BAPs, namely (3E,5E)‐1‐(4‐methylbenzenesulfonyl)‐3,5‐bis[4‐(trifluoromethyl)benzylidene]piperidin‐4‐one dichloromethane monosolvate, C28H21F6NO3S·CH2Cl2, ( 4 ), (3E,5E)‐1‐(4‐fluorobenzenesulfonyl)‐3,5‐bis[4‐(trifluoromethyl)benzylidene]piperidin‐4‐one, C27H18F7NO3S, ( 5 ), (3E,5E)‐1‐(4‐nitrobenzenesulfonyl)‐3,5‐bis[4‐(trifluoromethyl)benzylidene]piperidin‐4‐one, C27H18F6N2O5S, ( 6 ), and (3E,5E)‐1‐(4‐cyanobenzenesulfonyl)‐3,5‐bis[4‐(trifluoromethyl)benzylidene]piperidin‐4‐one dichloromethane monosolvate, C28H18F6N2O3S·CH2Cl2, ( 7 ), were prepared by Claisen–Schmidt condensation and N‐sulfonylation. They were characterized by NMR, FT–IR and HRMS (high resolution mass spectrometry). Single‐crystal structure analysis reveals that the two 4‐(trifluoromethyl)phenyl rings on both sides of the piperidone ring in ( 4 )–( 7 ) adopt an E stereochemistry of the olefinic double bonds. Molecules of both ( 4 ) and ( 6 ) are connected by hydrogen bonds into one‐dimensional chains. In ( 5 ) and ( 7 ), pairs of adjacent molecules embrace through intermolecular hydrogen bonds to form a bimolecular combination, which are further extended into a two‐dimensional sheet. The anti‐inflammatory activity data reveal that ( 4 )–( 7 ) significantly inhibit LPS‐induced interleukin (IL‐6) and tumour necrosis factor (TNF‐α) secretion. Most importantly, ( 6 ) and ( 7 ), with strong electron‐withdrawing substituents, display more potential inhibitory effects than ( 4 ) and ( 5 ). 相似文献
6.
Deepak Chopra T. P. Mohan B. Vishalakshi T. N. Guru Row 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(12):o704-o710
In the molecular structures of a series of substituted chalcones, namely (2E)‐3‐(2‐fluoro‐4‐phenoxyphenyl)‐1‐phenylprop‐2‐en‐1‐one, C21H15FO2, (I), (2E)‐3‐(2‐fluoro‐4‐phenoxyphenyl)‐1‐(4‐fluorophenyl)prop‐2‐en‐1‐one, C21H14F2O2, (II), (2E)‐1‐(4‐chlorophenyl)‐3‐(2‐fluoro‐4‐phenoxyphenyl)prop‐2‐en‐1‐one, C21H14ClFO2, (III), (2E)‐3‐(2‐fluoro‐4‐phenoxyphenyl)‐1‐(4‐methylphenyl)prop‐2‐en‐1‐one, C22H17FO2, (IV), and (2E)‐3‐(2‐fluoro‐4‐phenoxyphenyl)‐1‐(4‐methoxyphenyl)prop‐2‐en‐1‐one, C22H17FO3, (V), the configuration of the keto group with respect to the olefinic double bond is s‐cis. The molecules pack utilizing weak C—H...O and C—H...π intermolecular contacts. Identical packing motifs involving C—H...O interactions, forming both chains and dimers, along with C—H...π dimers and π–π aromatic interactions are observed in the fluoro, chloro and methyl derivatives. 相似文献
7.
Matrix solid‐phase dispersion with chitosan‐zinc oxide nanoparticles combined with flotation‐assisted dispersive liquid–liquid microextraction for the determination of 13 n‐alkanes in soil samples
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Mostafa Khajeh Hongyuan Yan Esmat Arefnejad Mousa Bohlooli 《Journal of separation science》2014,37(22):3292-3298
In this study, chitosan‐zinc oxide nanoparticles were used as a sorbent of miniaturized matrix solid‐phase dispersion combined with flotation‐assisted dispersive liquid–liquid microextraction for the simultaneous determination of 13 n‐alkanes such as C8H18 and C20H42 in soil samples. The solid samples were directly blended with the chitosan nanoparticles in the solid‐phase dispersion method. The eluent of solid‐phase dispersion was applied as the dispersive solvent for the following flotation‐assisted dispersive liquid–liquid microextraction for further purification and enrichment of the target compounds prior to gas chromatography with flame ionization detection. Under the optimum conditions, good linearity with correlation coefficients in the range 0.9991 < r2 < 0.9995 and low detection limits between 0.08 to 2.5 ng/g were achieved. The presented procedure combined the advantages of chitosan‐zinc oxide nanoparticles, solid‐phase dispersion and flotation‐assisted dispersive liquid–liquid microextraction, and could be applied for the determination of n‐alkanes in complicated soil samples with acceptable recoveries. 相似文献
8.
Rui‐Qin Fang Zhu‐Ping Xiao Ping Cao Da‐Hua Shi Hai‐Liang Zhu 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(5):m193-m194
In the title compound, {[Na(H2O)4]2(C4H2N2O7)}n, the 1,5‐dihydroxy‐4,8,9‐trioxa‐2,6‐diazabicyclo[3.3.1]nona‐2,6‐diene‐3,7‐diolate anion lies across a twofold axis in the space group C2/c; there are two independent Na sites, one on a twofold axis and the other on a centre of inversion. Hydrogen bonds link the {[Na(H2O)4]+}n chains and diolate anions into a three‐dimensional framework. 相似文献
9.
In the system of SDS/n-C5H11OH/n-C7H16/H2O with the weight ratio of SDS/n-C5H11OH/H2O system at5.0/47.5/47.5, the upper phase of the system was W/O microemulsion, and the lower phase was the bicontinuous microemulsion. When the n-heptane content was less than 1%, with the increase of the n-heptane content, the capacitance (Co, Cod) in the upper phase (W/O) dropped, the capacitance (CB1, CBld) in the lower phase (BI) raised. At the same time, the W/O-BI inteffacial potential (ΔE), capacitance (Ci), and charge-transfer current (ict) decreased.After the n-heptane content reached 1%, with the increase of the n-heptane content, ΔE, Ci and ict demonstrated no significant change. 相似文献
10.
Gabriella Cavallo Giancarlo Terraneo Alessandro Monfredini Marco Saccone Arri Priimagi Tullio Pilati Giuseppe Resnati Pierangelo Metrangolo Duncan W. Bruce 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(21):6408-6412
Unconventional ionic liquid crystals in which the liquid crystallinity is enabled by halogen‐bonded supramolecular anions [CnF2 n+1‐I⋅⋅⋅I⋅⋅⋅I‐CnF2 n+1]− are reported. The material system is unique in many ways, demonstrating for the first time 1) ionic, halogen‐bonded liquid crystals, and 2) imidazolium‐based ionic liquid crystals in which the occurrence of liquid crystallinity is not driven by the alkyl chains of the cation. 相似文献
11.
Polymeric fibers and microporous films by photo‐crosslinking of triphenylene‐derived liquid crystals
Takuji Hirose Zhe Xu Yuka Kikuchi Masahito Fukushima Kengo Kawamura Yosuke Kaguchi Koichi Kodama Mikio Yasutake 《Journal of polymer science. Part A, Polymer chemistry》2019,57(5):605-612
Two series of photoreactive discotic liquid crystals consisting of a triphenylene core and six cinnamate units with one ( TPC1 n ) or two ( TPC2 n ) n‐alkoxy groups (C nH2n+1O; n = 10–14), respectively, as peripheral groups are synthesized. Both of them are polymerized into fibers up to 2 mm long by UV irradiation in liquid paraffin in the columnar LC temperature ranges. The fiber structures seem to be preconstructed in liquid paraffin. In addition, TPC2 n are shown to form microporous films up to 15 μm in diameter by simply casting the solutions of some solvents followed by drying for several minutes in air at room temperature. Photoirradiation of the films in the LC temperature range converts them to polymeric ones while preserving the microporous and hexagonally ordered structure. From comparison with TPC1 n and the hydrogenated derivative of TPC2 12 , the porous film‐forming property is suggested to result from the combination of the double bond of the cinnamoyl group and the two long alkoxy chains on the phenyl ring. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 605–612 相似文献
12.
Dr. Gabriella Cavallo Prof. Dr. Giancarlo Terraneo Alessandro Monfredini Dr. Marco Saccone Prof. Dr. Arri Priimagi Dr. Tullio Pilati Prof. Dr. Giuseppe Resnati Prof. Dr. Pierangelo Metrangolo Prof. Dr. Duncan W. Bruce 《Angewandte Chemie (International ed. in English)》2016,55(21):6300-6304
Unconventional ionic liquid crystals in which the liquid crystallinity is enabled by halogen‐bonded supramolecular anions [CnF2 n+1‐I???I???I‐CnF2 n+1]? are reported. The material system is unique in many ways, demonstrating for the first time 1) ionic, halogen‐bonded liquid crystals, and 2) imidazolium‐based ionic liquid crystals in which the occurrence of liquid crystallinity is not driven by the alkyl chains of the cation. 相似文献
13.
Jos J. Campos‐Gaxiola Susana P. Arredondo Rea Ramn Corral Higuera Herbert Hpfl Adriana Cruz Enríquez 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(1):48-52
Two organic–inorganic hybrid compounds have been prepared by the combination of the 4‐[(E)‐2‐(pyridin‐1‐ium‐2‐yl)ethenyl]pyridinium cation with perhalometallate anions to give 4‐[(E)‐2‐(pyridin‐1‐ium‐2‐yl)ethenyl]pyridinium tetrachloridocobaltate(II), (C12H12N2)[CoCl4], (I), and 4‐[(E)‐2‐(pyridin‐1‐ium‐2‐yl)ethenyl]pyridinium tetrachloridozincate(II), (C12H12N2)[ZnCl4], (II). The compounds have been structurally characterized by single‐crystal X‐ray diffraction analysis, showing the formation of a three‐dimensional network through X—H...ClnM− (X = C, N+; n = 1, 2; M = CoII, ZnII) hydrogen‐bonding interactions and π–π stacking interactions. The title compounds were also characterized by FT–IR spectroscopy and thermogravimetric analysis (TGA). 相似文献
14.
Yoriko Sonoda Seiji Tsuzuki Nobuyuki Tamaoki Midori Goto 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(3):o196-o200
The crystal structures of the four E,Z,E isomers of 1‐(4‐alkoxyphenyl)‐6‐(4‐nitrophenyl)hexa‐1,3,5‐triene, namely (E,Z,E)‐1‐(4‐methoxyphenyl)‐6‐(4‐nitrophenyl)hexa‐1,3,5‐triene, C19H17NO3, (E,Z,E)‐1‐(4‐ethoxyphenyl)‐6‐(4‐nitrophenyl)hexa‐1,3,5‐triene, C20H19NO3, (E,Z,E)‐1‐(4‐nitrophenyl)‐6‐(4‐n‐propoxyphenyl)hexa‐1,3,5‐triene, C21H21NO3, and (E,Z,E)‐1‐(4‐n‐butoxyphenyl)‐6‐(4‐nitrophenyl)hexa‐1,3,5‐triene, C22H23NO3, have been determined. Intermolecular N⋯O dipole interactions between the nitro groups are observed for the methoxy derivative, while for the ethoxy derivative, two adjacent molecules are linked at both ends through N⋯O dipole–dipole interactions between the N atom of the nitro group and the O atom of the ethoxy group to form a supramolecular ring‐like structure. In the crystal structures of the n‐propoxy and n‐butoxy derivatives, the shortest intermolecular distances are those between the two O atoms of the alkoxy groups. Thus, the nearest two molecules form an S‐shaped supramolecular dimer in these crystal structures. 相似文献
15.
Magorzata Szczesio Andrzej Olczak Jolanta Goka Katarzyna Gobis Henryk Foks Marek L. Gwka 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(7):o235-o240
Methyl 2‐(pyrazin‐2‐ylcarbonyl)hydrazinecarbodithioate, C7H8N4OS2, (E1), N′‐[bis(methylsulfanyl)methylidene]pyrazine‐2‐carbohydrazide, C8H10N4OS2, (F1), N′‐[bis(methylsulfanyl)methylidene]‐6‐methoxypyrazine‐2‐carbohydrazide, C9H12N4O2S2, (F2), and methyl 1‐methyl‐2‐(pyrazin‐2‐ylcarbonyl)hydrazinecarbodithioate, C8H10N4OS2, (G1), can be considered as derivatives of classical (thio)amide‐type tuberculostatics, and all are moderately active against Mycobacterium tuberculosis. This study was undertaken in a search for relationships between activity and specific intramolecular interactions, especially conjugations and hydrogen‐bond contacts, and the molecular structures were compared with respective amine analogues, also active against the pathogen. Despite the differences between the amine and carbonyl groups with opposite functions in the hydrogen bond, the two types of structure show a surprisingly similar planar geometry, mostly due to the conjugations aided by the bifurcated intramolecular hydrogen‐bond contact between the N—H group of the central hydrazide group as donor and a pyrazine N atom and an S atom of the dithio function as acceptors. Planarity was suggested to be crucial for the tuberculostatic activity of these compounds. The N‐methylated derivative (G1) showed a significant twist at the N—N bond [torsion angle = −121.9 (3)°] due to the methyl substitution, which precludes an intramolecular N—H...S contact and the planarity of the whole molecule. Nonetheless, the compound shows moderate tuberculostatic activity. 相似文献
16.
Rui‐Yan Li Bing‐Qiang Wang Zhi‐Ru Li Di Wu Ying Li 《International journal of quantum chemistry》2008,108(1):151-160
Using the counterpoise‐corrected potential energy surface method, the stationary structures of the π Br‐bond complexes C2H4‐nFn? BrF (n = 0–2) with all real frequencies have been obtained at MP2/aug‐cc‐pVDZ level. The order of the π Br‐bond length is 2.625 Å (C2H4? BrF) < 2.714 Å (C2H3F? BrF) < 2.751 Å (g‐C2H2F2? BrF) < 2.771 Å (trans‐C2H2F2? BrF) < 2.778 Å (cis‐C2H2F2? BrF). The interaction energies (Eint) are, respectively,‐5.9 (C2H4? BrF),‐4.4 (C2H3F? BrF),‐3.7 (g‐C2H2F2? BrF),‐3.1 (cis‐C2H2F2? BrF),‐2.8 kcal/mol (trans‐C2H2F2? BrF), at the CCSD (T)/aug‐cc‐pVDZ level, which include larger electron correlation contributions (Ecorre). The order of Ecorre is‐3.40 (C2H4? BrF),‐3.60 (C2H3F? BrF),‐3.85 (g‐C2H2F2? BrF),‐3.86 (cis‐C2H2F2? BrF),‐3.88 kcal/mol (trans‐C2H2F2? BrF). The earlier results show above that the F substituent effect elongates the π Br‐bond, reduces the Eint, and increases the Ecorre contribution of the interaction energy. Interestingly, the interaction energy of the cis‐C2H2F2? BrF structure with longer interaction distance is larger than that of the corresponding trans‐C2H2F2? BrF structure with shorter interaction distance. This reason comes from a special secondary interaction between lone pairs of Br atom with positive charge and some atoms (H, C) with positive charges of C2H2F2 in the cis‐C2H2F2? BrF structure. Comparing with corresponding C2H4‐nFn? ClF and C2H4‐nFn? HF, the C2H4‐nFn? BrF system has the larger Eint in which main contribution comes from the larger Ecorre, representing the larger dispersion interaction. The larger Ecorre contribution of the Eint of π Br‐bond can be used to understand that the π Br‐bond is shorter and stronger than corresponding π Cl‐bond. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 相似文献
17.
Broad Hexagonal Columnar Mesophases Formation in Bioinspired Transition‐Metal Complexes of Simple Fatty Acid meta‐Octaester Derivatives of meso‐Tetraphenyl Porphyrins
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Dr. Bin Wu Keyang Chen Yuchen Deng Jian Chen Dr. Chengjie Liu Prof. Rongshi Cheng Prof.Dr. Dongzhong Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(9):3671-3681
A series of meta‐substituted fatty acid octaester derivatives and their transition‐metal complexes of meso‐ tetraphenyl porphyrins (TPP‐8OOCR, with R=Cn?1H2n?1, n=8, 12, or 16) have been prepared through very simple synthesis protocols. The thermotropic phase behavior and the liquid crystalline (LC) organization structures of the synthesized porphyrin derivatives were systematically investigated by a combination of differential scanning calorimetry (DSC), polarized optical microscopy (POM), and variable‐temperature small‐angle X‐ray scattering/wide‐angle X‐ray scattering (SAXS/WAXS) techniques. The shorter octanoic acid ester substituted porphyrin (C8‐TPP) did not show liquid crystallinity and its metal porphyrins exhibited an uncommon columnar mesophase. The lauric acid octaester (C12‐TPP) and the palmitic acid octaester (C16‐TPP) series porphyrins generated hexagonal columnar mesophase Colh. Moreover, the metal porphyrins C12‐TPPM and C16‐TPPM with M=Zn, Cu, or Ni, exhibited well‐organized Colh mesophases of broad LC temperature ranges increasing in the order of TPPNi<TPPCu≤TPPZn with their increased effective ionic radii in the square‐planar coordination. The simplicity in synthesis, the well intercolumnar organization of Colh mesophase, the broadness of the discotic LC range, and the specific UV/Vis absorption and fluorescence emission behaviors make the symmetrically substituted fatty acid octaester porphyrins and their metal complexes very attractive for variant applications. 相似文献
18.
Matthias Tamm Dejan Petrovic Eberhardt Herdtweck 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(5):m217-m219
The title compound, (C11H22N3)[FeCl3(C11H21N3)], is one of the rare examples where an isolated ionic pair of the type [A]n+[EMX3]n− (E is any non‐metal, M is any transition metal and X is any halogen) could be structurally characterized. Two short N—H⋯Cl contacts between the two ammonium H atoms and two of the three Cl atoms of the counter‐anion generate a six‐membered ring. The third Cl atom is involved in a weaker intramolecular hydrogen bond to the neutral 1,3‐diisopropyl‐4,5‐dimethyl‐4‐imidazolin‐2‐ylideneamine ligand. 相似文献
19.
Channappa N. Kavitha Hemmige S. Yathirajan Manpreet Kaur Eric C. Hosten Richard Betz Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(8):805-811
The structures of two salts of flunarizine, namely 1‐bis[(4‐fluorophenyl)methyl]‐4‐[(2E)‐3‐phenylprop‐2‐en‐1‐yl]piperazine, C26H26F2N2, are reported. In flunarizinium nicotinate {systematic name: 4‐bis[(4‐fluorophenyl)methyl]‐1‐[(2E)‐3‐phenylprop‐2‐en‐1‐yl]piperazin‐1‐ium pyridine‐3‐carboxylate}, C26H27F2N2+·C6H4NO2−, (I), the two ionic components are linked by a short charge‐assisted N—H...O hydrogen bond. The ion pairs are linked into a three‐dimensional framework structure by three independent C—H...O hydrogen bonds, augmented by C—H...π(arene) hydrogen bonds and an aromatic π–π stacking interaction. In flunarizinediium bis(4‐toluenesulfonate) dihydrate {systematic name: 1‐[bis(4‐fluorophenyl)methyl]‐4‐[(2E)‐3‐phenylprop‐2‐en‐1‐yl]piperazine‐1,4‐diium bis(4‐methylbenzenesulfonate) dihydrate}, C26H28F2N22+·2C7H7O3S−·2H2O, (II), one of the anions is disordered over two sites with occupancies of 0.832 (6) and 0.168 (6). The five independent components are linked into ribbons by two independent N—H...O hydrogen bonds and four independent O—H...O hydrogen bonds, and these ribbons are linked to form a three‐dimensional framework by two independent C—H...O hydrogen bonds, but C—H...π(arene) hydrogen bonds and aromatic π–π stacking interactions are absent from the structure of (II). Comparisons are made with some related structures. 相似文献
20.
Two highly fluorinated bipyridine derivatives, (4,4′‐bis(RfCH2OCH2)‐2,2′‐bpy) {Rf = n‐C10F21 ( 1a ), n‐C10F23 ( 1b )}, have been synthesized starting from 4,4′‐bis(BrCH2)‐2,2′‐bpy and the corresponding fluorinated alkoxides. The fluorine contents of ligands 1a‐b are 62.3% and 63.3%, respectively, both being white solids, virtually insoluble in CH2Cl2 or DMF and highly fluorophilic with a partition ratio between DMF and n‐C8F18 less than 1:1000. The reaction of ligands 1a‐b with [Pd(CH3CN)2Cl2] results in novel Pd complexes [PdCl2(4,4′‐bis‐(RfCH2OCH2)‐2,2′‐bpy)] where Rf = n‐C10F21 ( 2a ), n‐C10F23 ( 2b ), respectively. The Pd complexes 2a‐b are pale yellow solids, soluble only in fluorinated solvents. The Pd complexes 2a‐b have been satisfactorily tested for Mizoroki‐Heck arylation under fluorous biphasic catalysis conditions in that the Pd complexes 2a‐b are easily recovered and maintain good catalytic activity after 8 consecutive cycles (> 90% yield). The TGA studies indicate that the Pd complexes 2a‐b are thermally stable up to 300 °C. 相似文献